Device for acoustically detecting and tracing aircraft



June 7, 1932. H. M. J. BENARD ET AL- 1,351,680

DEVICE FOR ACOUSTICALLY DETECTING AND TRACING AIRCRAFT Filed July 24, 1930 Wm H man e1 I h 66 Patented June 7, 1932 uu'rrEo's'rAT s PATENT OFFICE HENRI LUGLIEN MARIE JOSEPH BEN'ARD .AlNDBE MABGELIN, OI PARIS, FRANCE DEVICE FOR ACOUSTICALIY DETECTING AND TRACING AIR/Owl i "Application filed July 24, 1930, Serial No. 470,487, and-in France April 17,1980.

As acoustic data. are never as accurate as optic data, it is important to be able to pass as soon as possible from acoustic to optic means for detecting and tracing an aircraft or the like. Consequently a detecting station should comprise both acoustic and optic detecting means.

The coordinates of the aircraft beingobtained acoustically or optically are transmitted either directly-to the apparatus requiring them such as a gun or a Searchlight or better still to, an intermediary apparatus which brings to these data the required corrections which allow them to be used directly by the gun or searchlight.

Our invention has for its object a device for connecting the apparatus to be conin order to take into account on one hand the so-called acoustic aberration phenomenon corresponding to the distance travelled over by the aircraft during the time required for the sound to reach the listener-in and on the other, hand any small irregularities in the acoustic laying.

Our complete arrangement is double and comprlses independent transmission means for the two coordinates of the air craft such as its azimuth and angle of sight. The two 1 transmission means are similar and we will describe only one of them hereinafter.

We have shown a preferred form of executionther eof, by way of example, in the' accompanying drawin Fig. 1 is a general iagrammatic view of the transmission means and Fig. 2 is a front view ofan element thereof.

The listening-in device is shown at 1, the

binocular sight glass forming the optic detecting means at 2 and the corrector to which the data from the preceding devices are to be transmitted at 3.

The listening in device is connected with the optic device through a rigid connection nected through a differential gear D The shaft 4' carries one of the sun wheels 6 and the shaft 5 the other sun wheel 7. The differentlal gear D is completed by two planet wheels 8 and 9 and by their rotary casing controlled through the inion 11 rotating integrally with the hand wheel 12.

To the shaft 4 is keyed a bevel pinion 13 controlling another pmion 14 keyed to a shaft 15 the other end of which carries a bevel (pmion 16 engaging a bevel pinion 17 carrie by a shaft 18 connected through the differential gear D to the shaft 19 controlling the corrector 3. The differential gear D comprises a sun wheel 20 keyed to the shaft 18 and a sun wheel 21 keyed to the shaft 19, said sunwheels being connected through the planet wheels 22 and 23, the casing 24 of the latter being set in any angular position through the lever 25.

The outer toothwork of the casing 24- meshes with a pinion 26 keyed to a shaft carrying one of thesunwheels 28 of a. third differential gear D The second sunwheel 29 thereof is carried by a shaft 30 to which is keyed a bevel wheel 31 meshing with the toothwork on the casing 10 of the differential casin D I The di erential gear D is completed by the two planet wheels 32-33 and by their casing 34 (Figs. 1 and 2) to which is directly secured a counterweight 35 adapted to move between'two adjustable stops 36-37 and of which the center of gravity may be raised or lowered;

A part 38 of the shaft 30 acts as a worm and meshes with a toothed wheel 39 carrying a hand 40 moving over a stationary scale 41 provided with a mark42.

The worln'ng. is as follows:

As soon as the aircraft is detected by the listeners-in at the acoustic detecting device 1, they keep the said device directed toward the air-craftby acting 'ontheir control hand wheels. Themovements'aretransmitted onone hand to the corrector 3 by the pinions 13 and 14, the shaft 15, the pinions 16 and 17, the shaft 18, the differential gear D of which neouslytransmitted to the hand 40 moving a certain recdom of operation and may by to it by the acoustic laying device 1. It is using his hand wheel 12 modif the position of his sight-glass with referen e to that given sufiicient therefore that he overcomes the resistance afforded by the counterweight 35 when acting on the shaft 5.

From this moment onwards and for a short time, the shafts 4 and 5 rotate at different speeds and the casing 10 of the differacting on it craft and henceforward t ential ear D gis driven at a speed equal to the difierence between the speeds of said shafts. This rotationis transmitted through the pinion 31 and the shaft to the sun wheel 29 of the differential gear D As the second sun wheel 28 of D, is locked by the lever 25 through the casing 24 of the differential D the pinion 26 and the shaft 27 the casing 34 secured to the planet wheels is rotated and raises the counterweight 35.

The rotation of the casing 10 is simultaover the scale 41.

In brief during this part of the operation corresponding to the'hearingxof the aircraft, the working is as follows: T e work effected by the optic observer at 2 in order to overcome the resistances against rotation of his hand wheel when he destroys the correspondency between the two detecting devices is stored in the counterweight 35'as potential energy formed in the field of gravity.

Now if when operating as stated, the observer at 2 finds the aircraft through 1118 sightglass, he continues acting on vhis handwheel 12 so as to keep his si 'htglass on the air he data provided thereby are'transmitted to the corrector 3 without the listening in device 1 ceasing to be operative.

To this end the observer at 2, as soon as he has seen the aircraft, releases the casing 24 of the differential D or causes it to be re- 'weight 35 in its'normal vertical position "where it remains stationary The movement 5' the casing 24. This movement-is added in leased through the actuation of the lever 25. The sunwheel 28 of the differential D being no lon or held stationary, the casing 34 is urged ack under the action of the counterof the sun-wheel 29 is transmitted to the sun wheel 28, to the shaft 27," the pinion 26 and difference in the laying of the si ht-glass with reference to the. listening-in eviceLgas laid during the first part of operation corresponding to the hearing of the aircraft;

(b) To ensure synchronism between the v sight-glass and the Corrector. r

The first condition is provided b the variation in the potential energy of t e counterweight 35 at the moment ofthe release of the casing 24 and the second by the mechanical connection between the optic apparatus and the corrector through the agency of the three differential gears.

Lastly it may happen that the observer at the station 2 loses sight of the aircraft. It is therefore necessary to return to the first modus operandi by synchronizing again the listening-in device with the 0 tie device and disconnecting the corrector rom the optic device. To this end we return through the handwheel 12, the hand 40 in front of its mark 42 so as to remove the angular shifting detecting device and the lever 25 is then caused to lock the casing 24 of the differential D in the position assumed by it.

Of course the above described device may be considerably modified: thus any-type of differential (with bevel or straight pinions, etc.) may be used, the hand 40 may be conof the corrector with reference to the acoustic trolled otherwise than through a worm gear as shown; the counterweight 35 may be replaced by any other means adapted to store up energy, such as a spring, a compressible fluid, etc.

What we claim is: I

1. A combined optical and acoustic detecting device comprising a listening-in device, an optic detecting device, a receiver shaft, a connection whereb the listening. in device controls the optic etecting device, means for actuating the optic device independently of the listening-in device, a resistant device against which the said independent actuation is eifected and adapted to store energy up I thereby, means whereby the data given out by the optic device are transmitted throughthis resistant device to the receiver shaft, means for synchronizing when desired the-receiver shaft with the listener-in device and means for returning the whole arrangement to its original position. 2-. A combined optical and acoustic detectmg device comprising a listening-in device,

an optic detecting device, a receiver shaft, a the third difierential and adapted to move first differential connecting the two first do on either side of the vertical whereby it forms vices, a second differential connecting the energy storing means, adjustable stops limitlistenin -in device and the receiver shaft, ing the angular movement of the countera thir differential connecting the two weight and a handwheel controlling the rotaformer and including sun wheels operation of the first differential.

tively connected with the planet wheel In testimony whereof we have afiixed our casing of the other differentials respectively, signatures.

means operable at will for locking the planet wheel casing of the second differentlal, a resistant device adapted to store energy and connected with the planet wheel casing of the third differential and means for returning the two first devices into their ori inal relative position. 7 r r 3. A combined optical and acoustic detecting device comprising a listening-in device, an optic detecting device, a receiver shaft, a first difi'erential connecting the two first devices, a second differential connecting the listenin -in device and the receiver shaft, a thir difl'erential connecting the two former and including sunwheels operatively connected with the planet wheel casing of the other differentials respectively, means operable at will for locking the planet wheel casing of the second differential, a resistant device adapted to store energy and connected with the planet wheel casing of the 80 third differential and a handwheel controlling thel planet wheel casing of the first diiierentia 4. A combined optical and acoustic detecting device comprising a listening-in device, an optic detecting device, a receiver shaft, a first differential connecting the two first devices, a second differential connecting the listening-in device and the receiver shaft, a third differential connecting the two former and including sunwheels operatively connected with the planet wheel casing of the other difierential respectively, means operable at will for locking the planet wheel casing of the second differential, a resistant device adapted to store energy and connected with the planet wheel casing of the third differential, a hand controlled by the planet wheel casing of the first differential, a. scale cooperating therewith and provided with a mark and a handwheel. controlling the planet wheel casing of the first differential and adapted to return the hand over its mark.

5. A combined optical and acoustic detecting device" comprising a listening-in device, an optic detecting device, a receiver shaft, a first differential connecting the two first de- .vices, a second differential connecting the listening-in device and the receiver shaft, a

third diiferential connecting the two former and including sunwheels operatively con nected with the planet wheel casing of the other differentials respectively, means operable at will for locking the planet wheel casing of the second differential, a counterweight secured directly to the planet wheel casing of msmu LUGLIEN MARIE JOSEPH 312mm. ANDRE wuss mncruu. 

